Recent questions tagged where

I have purchased a Samsung Galaxy S4 with AT&T GSM provider on a contract. My phone is locked. I cannot use any other sim card but the AT& T. is there any way to unlock my phone in free and use any sim I wish to use.

I have been using the Nokia Lumia 900 for a while. I use my phone for browsing a lot. I also play some games on it. I think because of this my phone gets heated up. Which I think is not good. How can i reduce the overheating problem in Nokia Lumia 900?